“It usually takes about 20 minutes to get to the city,” we find ourselves saying when asked where we take the train from. But how long does it actually take? That was the itch – this map is the scratch.

What’s extremely valuable about this exercise is it highlights just how few of the stations within the 30-minute envelope have high residential densities, even though they provide access to circa 300,000 jobs in the CBD. For example, the in-carriage travel time to Flinders Street station on an all-stopper service is only 19 minutes but look at the absence of any higher density development close to Alphington station.

Some maps showing cycling patterns in Melbourne of those riding to work. Data from Census2016

Another very valuable mapping exercise because it shows that workers who commute by bicycle overwhelmingly live in the inner city and inner suburbs. That helps explain why journeys to work by bicycle mostly replace trips by public transport, not by car. Zoom out and you can see the data – and a similar pattern – in other Australian cities. Like voting in the SSM survey, there’s a strong geographical dimension.

Here’s another map from the Institute for Sensible Transport, showing that in some (very small) areas of inner northern Melbourne the mode share of cycling for the journey to work was up around 20%.

We already know a high proportion of cycling commuters work in or close to the city centre, so it would be useful to see an estimate of the net benefits from achieving (say) a 30% cycling mode share for commutes originating within 10 km of the CBD, especially in terms of dollar savings to the state budget. That sort of exercise might have some political heft; have our universities already done it?

According to a drastic road safety plan 30 kilometer per hour should be the speed limit in the entire Brussels’ region. The only exception should be the larger through roads. The plan by Brussels Minister for Road Safety Bianca Debaets (CD&V) and Minister for Mobility Pascal Smet (PS), joins the similar proposal by parliament member Bruno De Lille (Groen), and will be discussed in the Brussels’ government next week.

Great idea but the heading is misleading; this is a plan rather than a done deal. Moreover, the term “region” seems to refer to the City of Brussels, which covers 32 sq km, about the same area as the City of Melbourne (36 sq km).

A 30 kph limit across all or most of the circa 2,500 sq km that comprises urbanised Melbourne would be a bridge too far politically, just as it probably is in metropolitan Brussels too. The City of Melbourne is a more plausible candidate. It has a 40 kph limit in the Hoddle Grid and is planning to extend it to South Yarra. There are still roads in the CBD like Victoria Pde, though, that carry a lot of through traffic and have a 60 kph limit.

I think there’s a strong case for a 30 kph limit in areas where there’s high pedestrian activity. The risk of a pedestrian dying if struck by a car travelling at 30 kph is around 10%, compared to 30% at 40 kph, 60% at 50 kph, and 90% at 60 kph. A Monash Accident Research Unit project concluded that a reduction in average travel speed brought about by reducing urban speed limits is only likely to have a marginal impact on travel time:

Research tends to support this notion given that average speeds are influenced by many other factors including driver attitudes and preferences; roadway design; forms of traffic regulation at intersections; and prevailing traffic conditions (levels of congestion; weather; etc). Research studies in Australia in relation to the then proposed reduction of the default urban speed limit from 60 to 50 km/h, indicated only minimal impact on individual travel times and large benefits to society as a result of the reduction in crash trauma.

We shouldn’t be shy about slower average speeds for cars, trucks and buses. Public transport is substantially slower end-to-end for the great majority of trips than private transport, yet governments are investing in improvements because it has social advantages (see What’s government done to make public transport better?). We should use the same logic to justify lower speed limits for roads i.e. the amenity, safety and environmental benefits of slower traffic are likely to exceed the time costs.

The state government will move to allow highly automated vehicles to be driven on public roads under organised trial conditions, in changes to the Road Safety Act due to be introduced in Parliament on Tuesday.

Smart move for a state that still has an important role in international automotive design and research, but well behind some other jurisdictions that’ve shown a more receptive attitude to “humanless cars”.

The bigger issue though is to ensure autonomous vehicles provide a net benefit. In my view, that requires ensuring (a) they can’t be privately owned but must operate like hire cars, and (b) passengers pay per km/minute for the full cost of their travel. The question of how roadside activities are affected in the interests of making roads “readable” to vehicle AI also needs to be examined closely (see How will driverless cars change our cities?).

The Coalition is investigating the possibility of combining the North East Link road project with a rebooted East West Link if elected at the end of 2018. But Mr Guy emphasised that the controversial $5.8 billion East West Link – which was spiked by the Andrews government at a cost of more than $1 billion – was his party’s priority.

The East West Link isn’t dead, it’s restin’. With a state election next year, Opposition Leader Mathew Guy is set to marry public concern with traffic congestion to the Government’s decision to pay over $1 Billion to cancel the East West Link contract signed by the former Napthine Government.

The key problem with the East West Link back in 2014 was that it had an appalling Benefit Cost Ratio (see What can we learn from the East-West Link debacle?). Nothing’s changed to suggest it’s viability might’ve improved. Indeed, there’s a new problem; the North East Link.

It’s likely to fulfil a large part of the function that the East West Link might have delivered. It’s possible that building both, as Mr Guy says he might do, could blow the BCRs for both projects out of the water.

One of the arguments being trotted out now is that the 2014 election was a referendum on the East West Link and the project was lost for ever more. That might be a political appealing line but it’s wrong. It’s no more valid than claiming the public have shown they’re against an airport rail line because the Napthine Government also promised at the election it’d build one.

The East West Link was just one issue among many that voters across the state and across Melbourne considered in the lead up to polling day. There’s no way to reliably isolate what the result says about voter attitudes on a specific issue like this.

Labor’s state-wide two party preferred share of the vote went up by around 3.5% percentage points and the Green’s share didn’t change. That’s enough to change government in a two-party system because of the geography of electorates, but it doesn’t tell us how much weight the Victorian electorate gave to this specific issue or what their view on it was.

In any event, opinion polls consistently show that other issues, like health and education, are more important to Victorians than transport.

What can be reasonably claimed from the election result is that it gave Daniel Andrews (a) a mandate to repudiate the East West Link contract; and (b) he would’ve broken a clear promise if he consented to the project going ahead.

I think it’s also reasonable to infer that the East West Link was a very important issue for voters living in the inner city. But they’re only around 5% of all the electors who determine the make-up of the Victorian Parliament and the government. It’s also reasonable to pin the Government on the scale of compensation it ended up paying; that wasn’t disclosed at the election.

If you want to go ahead and use a ladder even though you do not know what you are doing, wear a helmet. Even if you think you know what you are doing, wear a helmet. I’m not joking.

Falls off ladders is my go-to example in debates on the mandatory helmet law for cyclists. It illustrates that we’re prepared to tolerate other cases where there’s a risk of severe personal injury without feeling it’s necessary to pass a Molly Law compelling climbers to wear a helmet. It might be because it’d be too hard to enforce or too invasive, but nevertheless we’re prepared to overlook it and cop the associated personal and social costs.

My conclusion is bicycle helmet advocates “got lucky” in the early 90s when they got the law changed. Now that it’s been in place for 25 years I don’t think the likelihood of repeal is high. While I sympathise with those who find the law intrusive and discriminatory, in the absence of convincing evidence that repeal would significantly boost cycling, my view is the debate is a distraction. The key issue is far and away cycling infrastructure (see also Is the bicycle helmet law such a big deal?).

It strikes me as sensible advice to wear a helmet on a ladder, especially for older climbers whose sense of balance and strength might’ve diminished. Head injuries are common enough from simple falls, much less ones from elevation.

The minister said recommendations of a Community Open Space Expert Panel set up to oversee the new open spaces would allow for “the greening up parts of Melbourne that has not had as much open space as other parts of the city.”

Planners and some people (like the members of my household) put a high value on proximity to open space, but I’m not sure most people do. There’s no doubt Australians put a premium on views over parks, but the increment in property value added by a park decays very quickly with distance. The relatively low provision of open space in places like Manhattan and Paris doesn’t prevent them from being among the most highly sought-after residential locations in the world.

We probably won’t know until there’s an election how much value the residents of neighbourhoods close to Skyrail put on the open space as an offset to the visual and aural intrusion of elevating the rail line. It’s complicated because it must be disentangled from the benefit of having the level crossing removed. Few see having more open space as a negative, but how many see it as a significant benefit?

I expect the facilities the Minister’s announced, including rock climbing, skating and sports courts, will be what appeals most to the locals.

Three of the new Emerald class ferries have been named after Australian doctors: heart surgeon Victor Chang; obstetrician Catherine Hamlin; and ophthalmologist Fred Hollows. Two have been named for the indigenous leaders Pemulwuy and Bungaree. But Transport Minister Andrew Constance announced on Tuesday the last vessel would be given the joke name Ferry McFerryface following a public competition attracting 15,000 suggestions.

This is up there with Tony Abbott awarding Prince Philip a Knight of the Order of Australia. It’s poor judgement because it’s ‘immortalising’ a passing fad and, moreover, there’s no local connection. It leaves the NSW Government open to the criticism it doesn’t take public transport, or those who work in it, seriously. And if you’re going to crack a joke, make sure it’s funny; tired and derivative doesn’t cut it.

However, talk to women all over the world about their walking habits, and one issue comes up again and again: personal safety.

Personal safety might also be part of the explanation for the difference in driving between millennial women and men (see also Can design make cities safe for women?). A study of millennial’s travel behaviour in six countries from the nineties to the noughties by Kuhnimhof et al found that in the 1990s, young men were more likely to have a license than young women in all the countries studied. This has reversed in Germany and the USA, and has almost levelled out in most other countries.

They also found that while both sexes generally drove less over the period, millennial men turned away from driving in greater numbers than millennial women (see Are millennials travelling less?).

Travel by males fell markedly in five of the countries over the period (young men now drive more in Norway). Kilometres driven by millennial women also fell. However, the fall in women’s driving was generally smaller than that for men and wasn’t observed in all countries. In particular, there was barely any change in France and Japan.

One consequence is that American and German women of this generation now drive as much as their male counterparts. This is a turnaround from the nineties when men in those countries drove noticeably more.

Arup decided to negotiate a settlement after the engineering and design group’s former lead traffic forecaster, Gerard Cavanagh, acknowledged under cross-examination in the Federal Court that the traffic models devised for Airport Link were “totally and utterly absurd” and that some of its forecasts were “simply ridiculous”.

This case has prompted the usual claims that the failure of Brisbane’s Airport Link (along with other failed tollway projects like Brisbane’s Clem7 and Sydney’s Lane Cove and Cross City tunnels) proves there are fundamental flaws in the standard way future traffic’s been modelled for the last 50 years. There are legitimate criticisms of all forms of modelling, but in this case the accusation misses the real cause; the way these projects were financed (see Why does yet another toll road look like it might fail?).

Note first that Brisbane transport firm Veitch Lister published independent forecasts for Airport Link and Clem7 that were much closer to the real-life outcome than those that investors relied on. For example, Veitch Lister forecast circa 60,000 vehicles per day post ramp-up. That compares with a claim of 195,000 vehicles per day in the proponent’s Product Disclosure Statement.

So, some inherent defect in the nature of modelling wasn’t the problem. The $89 million in underwriting and associated fees mentioned in the Airport Link Product Disclosure Statement hints at the key explanation. Professor John Goldberg suggests we should look at the way projects are packaged:

The public-private partnership concept has failed in Australia and should serve as a warning to superannuation funds of the high risk of investment in road infrastructure. A common flaw in the failed tolls roads and, notably, Airport Link, is the use of a “work back” philosophy to forecasting traffic numbers…. The promised return on equity to investors is a starting point used to work back to how much revenue must be generated from the expected daily flow of vehicles, which has been inflated to wildly unrealistic targets.

“Typically governments pick a promising part of their country, ideally one that has a big university nearby, and provide a pot of money that is meant to kick-start entrepreneurship under the guiding hand of benevolent bureaucrats….It has been an abysmal failure….Experts at Insead looked at efforts by the German government to create biotechnology clusters on a par with those found in California and concluded that ‘Germany has essentially wasted $20 billion—and now Singapore is well on its way to doing the same.’”

Barely any of the tech parks built to date in Australia have succeeded in terms of their original justification. They haven’t fostered innovation; they haven’t created links between academic researchers and start-ups; and they haven’t promoted productive partnerships between the firms located within them.

Almost all those claimed as “successes” in Australia are merely business parks. They’ve been successful only in real estate terms – they’ve sold land, attracted tenants and made a profit on the development.

In part they fail because the exemplars like Silicon Valley are unique. As explained in any number of books (e.g. Tom Wolfe’s Hooking Up), Silicon Valley grew organically and unselfconsciously in response to special conditions like unprecedented defence spending, a specific stage in the development of semi conductors, a particular collection of research institutions, and more.

The idea that a single small park associated with a single unexceptional university could somehow capture whatever is going on in an expansive region like Silicon Valley should give proponents pause for thought.

It’s also likely that the connections between firms, universities and research institutions in some of the famous districts aren’t as important as is commonly assumed. An alternative explanation is they located in the same place for the same reasons rather than because of each other.

The confluence of industry policy and urban policy – both highly politicised areas – must be a snake-oil seller’s dream!

What seems to matter most for innovation in the technology sector is being in a metropolitan area – the same “labour shed” – rather than paying the high costs of being cheek-by-jowl with each other or with key institutions. Very close proximity like that in the CBD seems to matter a lot for industries like finance, insurance, business services and media, but not for all industries or even most.

More than any other area in Australia, the people of western Sydney voted “no”. Here, where up to three quarters of the population in the electorates of Blaxland and Watson voted against same sex marriage, the cultural clash of marriage equality and the conservative values of immigrant cultures told the story of the polls.

The clustering of majority ‘no’ vote electorates in Western Sydney suggests a couple of possibilities. One is that people increasingly locate with others who share common values; it isn’t just an inner city thing. This could be one of the most important ways cities change in the future (see Are bigger cities less diverse? and Diversity in cities: does it have to be uniform?). The other is that the “three Sydneys” model proposed in the Greater Sydney Commission’s draft plan reinforces this idea of separation. There have to be serious doubts about whether this is a sensible idea for building social cohesion.